Many image or light capture devices have 3D or depth sensors or cameras that can form a 3D space of a scene, measure the distance from the camera to an object in a scene, and/or provide dimensions of an object in a scene. This occurs frequently in industrial or commercial settings, such as with the measurement of boxes or containers. In these situations where such measurement of objects such as boxes occurs at high frequencies, expensive precision equipment is usually used, such as laser scanners. Such equipment, however, is not practical for the small consumer product nor affordable.
Other conventional three dimensional systems exist but are not practical for box measurement either. For example, some game consoles use a separate motion sensing panel dedicated to forming an object or scene in a three-dimensional grid and formed by using a sequence of images. The panel is typically fixed in position to reduce signal-to-noise ratio and requires an object to be moved to the field of view of the panel, which may be an inconvenience or an impossibility to the user. Also, whether or not the panel is fixed in position, the need to move or rotate the object, or to move the camera around the object to take many images of the object at different angles, also is inconvenient. Thus, such a system is no more convenient than simply measuring an object manually with a tape measure. Also, these types of panel cameras often have algorithms that cause inaccuracies including data smoothing that tends to literally and undesirably smooth corners of the image of an object resulting in the rounding of sharp edges and corners on a box being measured thereby erroneously reducing the length (corner to corner dimension) of the side on the box.
Smaller conventional depth cameras on a single device, such as a smart phone or dedicated digital camera, could be used to perform such object dimensioning. Such a conventional depth camera typically perform depth measurement by using a stereoscopic system that uses triangulation algorithms to form a depth map. Other methods to generate a depth image, such as from a single camera, also are known. These devices, however, often have sparse depth points, depth holes of missing depth data, and/or limited depth range or precision areas due to the limitations of the camera lens, sensors, and/or algorithms on such smaller, less expensive devices, often resulting in inaccurate object dimension measurements. Other significant errors can be caused by shaking the smartphone too much while holding the smart phone in the hand.